Radio communications between a gateway and a mobile terminal, e.g., in an airplane require tight control of transmit frequencies in order to provide a reliable communications link and to avoid interference between neighboring transmission channels. The carrier frequency of a transmitted signal, as transmitted by a mobile terminal, is subject to a Doppler frequency shift related to the location and velocity of the mobile terminal. The Doppler shift can be large compared to the available budget for the frequency variation of transmissions, and may use most of, or exceed, this budget. Further, a gateway may communicate with multiple mobile terminals, each with a different Doppler shift, making compensation at the gateway difficult.